This invention relates to compositions and methods for removing stains from fabric fibers. More particularly, this invention relates to compositions and methods for the removal of permanent red food dye stains from fibers.
Many substances that come in contact with fabric fibers, such as carpets, leave what has been considered indelible or permanent discoloration on the fibers. One of the most persistent or permanent stains is that formed by FD&C Red #40. According to 21 CFR 74.340, this color additive is principally the disodium salt of 6-hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo]-2-naphthalene-sulfonic acid. This azo dye is approved for use in foods, drugs and cosmetics when used in amounts consistent with good manufacturing practices. For example, FD&C Red #40 is used in numerous unsweetened Kool-Aid brand drink mixes, e.g. apple, black cherry, cherry, grape, orange, pink lemonade, raspberry, strawberry and tropical punch, and, in sugar sweetened Kool-Aid brand drink mixes, e.g. apple, cherry, grape, pink lemonade, raspberry, strawberry and tropical punch. It is also present in numerous other beverages, foods, drugs and cosmetics from a variety of manufacturers. Also, there are other colorants or dyes, both synthetic and natural which indelibly stain fabric fibers. Natural reddish stains from raspberry, cranberry, boysenberry and cherry juices are but examples of various substances which can cause staining of fibers.
These stains are often difficult, if not impossible, to remove without changing the color of the original fabric material. In many instances, even if the stain is wholly or partially removed, the coloring used to dye the fabric initially is also affected and the area where the stain was appears different from the remainder of the fabric.
Most manufacturers of food products acknowledge that stains on carpeting caused by food coloring are very difficult to remove unless immediate action is taken. Generally, they advise blotting up as much of the staining material from the affected area as possible with an absorbent material such as a towel. The area spilled upon is then repeatedly sponged with clean cold water. If that is insufficient to remove all stain coloration, many household cleaning books or manufacturer's instructions suggest using diluted solutions of acetic acid (white vinegar) or citric acid (lemon juice) and water. Others suggest using a mixture of alcohol and water. Some also suggest that when the carpet or other fabric is dry, to sponge with a detergent and water solution. In many cases, these procedures are repeated many times to no avail. Other suggested methods, which are impractical for large items such as carpets, include pouring boiling water from a height of at least three feet above the fabric through the fabric to quickly remove fruit stains before they set. As a last resort, it is suggested that bleaching agents such as hydrogen peroxide combined with ammonia be applied to dampened fabric containing the stain. Even if such treatment is effective, it may only lighten the stain and not remove it. Such drastic treatment may also bleach original color from the fibers.
Even when following the above suggestions, dyes such as FD&C Red #40 may resist all treatment and, in many cases, the only way to remove stains is to remove or replace the carpet or other fabric. In fact, more carpets are replaced because of stains which cannot be removed than from carpets being worn out.